TPS monitoring in metastatic breast cancer

The management of metastatic breast cancer patients reflects the heterogeneous nature of the disease. While patients may benefit from hormonal treatment, in most cases more toxic chemotherapy is applied in the advanced stages. The pretreatment levels of TPS in patients with metastatic breast cancer are correlated with prognosis. Decreasing TPS levels (> 50%) during treatment are indicative of response. The fastest decrease in TPS levels is obtained in patients with a favorable prognosis. Increasing TPS levels (> 25%) predict disease progression with a considerable lead time (median 8 months). The clinical impact of these observations is discussed in this paper.